Supercharging of internal combustion engines has frequently been used to help the fuel burn more completely and to make the engine produce more power. The supercharging usually operates by compressing the air fed into the cylinder or cylinders, as by charging the crankcase. See, for example, the article entitled "Webra T4 Four Cycle" commencing at Page 32 of the May, 1981 issue of "Model Airplane News".
In addition, some prior engines have utilized a passage connecting a crankcase outlet with an air inlet to the engine cylinder to provide the supercharging function. A one way valve, such as a reed valve, has been positioned at the crankcase outlet, and an inlet pot or surge tank has been disposed centrally within the passage, as disclosed in a Japanese article by Dr. Watanabe entitled "Improvement of Volumetric Efficiency of 4-Stroke Cycle Engine by Crankcase Supercharging".
Furthermore, atmosphere-connected jet pumps have been used in two cycle engines, to assist in providing fuel-free air to the cylinder chamber of the engine, as in the Henrikson U.S. Pat. No. 3,257,996.